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      <h2><a href="./">Go by Example 中文版</a>: 数组</h2>
      
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            <p>在 Go 中，<em>数组</em> 是一个具有编号且长度固定的元素序列。</p>

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            <a href="http://play.golang.org/p/SpnfbVgbjyr"><img title="Run code" src="play.png" class="run" /></a><img title="Copy code" src="clipboard.png" class="copy" />
          <div class="highlight"><pre><span class="kn">package</span> <span class="nx">main</span>
</pre></div>

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          <div class="highlight"><pre><span class="kn">import</span> <span class="s">&quot;fmt&quot;</span>
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          <div class="highlight"><pre><span class="kd">func</span> <span class="nx">main</span><span class="p">()</span> <span class="p">{</span>
</pre></div>

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            <p>这里我们创建了一个刚好可以存放 5 个 <code>int</code> 元素的数组 <code>a</code>。
元素的类型和长度都是数组类型的一部分。
数组默认值是零值，对于 <code>int</code> 数组来说，元素的零值是 <code>0</code>。</p>

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          <div class="highlight"><pre>    <span class="kd">var</span> <span class="nx">a</span> <span class="p">[</span><span class="mi">5</span><span class="p">]</span><span class="kt">int</span>
    <span class="nx">fmt</span><span class="p">.</span><span class="nx">Println</span><span class="p">(</span><span class="s">&quot;emp:&quot;</span><span class="p">,</span> <span class="nx">a</span><span class="p">)</span>
</pre></div>

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            <p>我们可以使用 <code>array[index] = value</code> 语法来设置数组指定位置的值，
或者用 <code>array[index]</code> 得到值。</p>

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          <div class="highlight"><pre>    <span class="nx">a</span><span class="p">[</span><span class="mi">4</span><span class="p">]</span> <span class="p">=</span> <span class="mi">100</span>
    <span class="nx">fmt</span><span class="p">.</span><span class="nx">Println</span><span class="p">(</span><span class="s">&quot;set:&quot;</span><span class="p">,</span> <span class="nx">a</span><span class="p">)</span>
    <span class="nx">fmt</span><span class="p">.</span><span class="nx">Println</span><span class="p">(</span><span class="s">&quot;get:&quot;</span><span class="p">,</span> <span class="nx">a</span><span class="p">[</span><span class="mi">4</span><span class="p">])</span>
</pre></div>

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            <p>内置函数 <code>len</code> 可以返回数组的长度。</p>

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          <div class="highlight"><pre>    <span class="nx">fmt</span><span class="p">.</span><span class="nx">Println</span><span class="p">(</span><span class="s">&quot;len:&quot;</span><span class="p">,</span> <span class="nb">len</span><span class="p">(</span><span class="nx">a</span><span class="p">))</span>
</pre></div>

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            <p>使用这个语法在一行内声明并初始化一个数组。</p>

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          <div class="highlight"><pre>    <span class="nx">b</span> <span class="o">:=</span> <span class="p">[</span><span class="mi">5</span><span class="p">]</span><span class="kt">int</span><span class="p">{</span><span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">,</span> <span class="mi">3</span><span class="p">,</span> <span class="mi">4</span><span class="p">,</span> <span class="mi">5</span><span class="p">}</span>
    <span class="nx">fmt</span><span class="p">.</span><span class="nx">Println</span><span class="p">(</span><span class="s">&quot;dcl:&quot;</span><span class="p">,</span> <span class="nx">b</span><span class="p">)</span>
</pre></div>

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            <p>数组类型是一维的，但是你可以组合构造多维的数据结构。</p>

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          <div class="highlight"><pre>    <span class="kd">var</span> <span class="nx">twoD</span> <span class="p">[</span><span class="mi">2</span><span class="p">][</span><span class="mi">3</span><span class="p">]</span><span class="kt">int</span>
    <span class="k">for</span> <span class="nx">i</span> <span class="o">:=</span> <span class="mi">0</span><span class="p">;</span> <span class="nx">i</span> <span class="p">&lt;</span> <span class="mi">2</span><span class="p">;</span> <span class="nx">i</span><span class="o">++</span> <span class="p">{</span>
        <span class="k">for</span> <span class="nx">j</span> <span class="o">:=</span> <span class="mi">0</span><span class="p">;</span> <span class="nx">j</span> <span class="p">&lt;</span> <span class="mi">3</span><span class="p">;</span> <span class="nx">j</span><span class="o">++</span> <span class="p">{</span>
            <span class="nx">twoD</span><span class="p">[</span><span class="nx">i</span><span class="p">][</span><span class="nx">j</span><span class="p">]</span> <span class="p">=</span> <span class="nx">i</span> <span class="o">+</span> <span class="nx">j</span>
        <span class="p">}</span>
    <span class="p">}</span>
    <span class="nx">fmt</span><span class="p">.</span><span class="nx">Println</span><span class="p">(</span><span class="s">&quot;2d: &quot;</span><span class="p">,</span> <span class="nx">twoD</span><span class="p">)</span>
<span class="p">}</span>
</pre></div>

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            <p>注意，使用 <code>fmt.Println</code> 打印数组时，会按照 <code>[v1 v2 v3 ...]</code> 的格式打印。</p>

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          <div class="highlight"><pre><span class="gp">$</span> go run arrays.go
<span class="go">emp: [0 0 0 0 0]</span>
<span class="go">set: [0 0 0 0 100]</span>
<span class="go">get: 100</span>
<span class="go">len: 5</span>
<span class="go">dcl: [1 2 3 4 5]</span>
<span class="go">2d:  [[0 1 2] [1 2 3]]</span>
</pre></div>

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            <p>在 Go 程序中，相较于数组，用得更多的是 _切片(slice)_。我们接着来看切片。</p>

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        下一个例子: <a href="slices">切片</a>
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